Rotary pump, compressor and the like



March 7, 1967 p. STEADMAN ROTARY PUMP, COMPRESSOR AND THE LIKE Filed Oct. 5. 1965 YINVENTOR Si'eodmun ATTORNEY United States Patent Ofiiice 3,307,487 Fatented Mar. 7, 1967 The present invention relates to improvements in rotary compressors, pumps, engines and similar expansible chamber devices, and more particularly to a double acting rotary compressor for use in refrigerating compressor units capable of being driven by a small electric motor.

One object is to provide a rotary compressor of the double acting type which comprises comparatively few parts which can be manufactured at a minimum of cost, but which will achieve a high degree of efficiency.

Another object is to provide a rotary compressor having a floatingly mounted vane carried by a rotor and in which the vane is solely supported within a radial slot in the rotor without the used extraneous devices such as casing wall guided cages directly connected with the vane and similar devices requiring extensive alteration of the rotor and compressor casing walls.

Another object resides in the provision of a rotary compressor in which the floatingly mounted vane or the like is solely guided in a radial slot in the rotor and which is shaped such that the same will be automatically wear compensating, thus increasing the life expectancy of the compressor and eliminating the frequent replacement of bearing seals and the like.

Another object is to provide a rotary compressor and the like having a unique porting system in which the discharge from one side of the rotor is conducted through the intake of the other side if desired, or the intakes connected to a common supply duct and the discharge ports connected to a common discharge duct without changing the direction of the compressor fluid or gas.

Another object is to provide a rotary compressor or pump unit in which the radial walls of the rotor are in sealing contact with radially extending sealing strips mounted in the casing wall of the chamber in such a manner as to have a rubbing contact therewith to effectively seal the pump and rotor at radially displaced opposed locations. I

Another object is to provide a rotary compressor unit or the like in which the rotor is provided with a circumferentially extending sealing ring affixed to the rotor to rotate therewith and seal the peripheral edge of the rotor in bearing contactual engagement with the inner peripheral wall of the stator or compressor housing.

Another object is to provide a rotary compressor unit in which the rotor is provided with spherically shaped hub portions which are received in correspondingly shaped recesses in the chamber walls of the housing, and which are provided with packing rings yieldingly urged into engagement with the spherical hub portions and thereby seal the compressor bearings for the rotary shaft.

Another object is to provide a rotary compressor, pump or the like in which the housing is formed of a circumferentially divided pair of sections bolted or otherwise aflixed one'to the other and in which housing may be a duplicate of the other during manufacture with one thereof displaced an angular distance of 180 with the bearing portions arranged at an acute angle to the radial plane of the circumferentially divided housing.

Another object is to provide a packing strip for the inner end or edge of the radial vane or blade, which strip is arcuately curved to conform to a spherical portion of the hub of the vane and to correspondingly curved inner Wall of the vane supporting radial slot.

unit having at least one piston member or vane which is floatingly mounted for movement in a direction laterally of the rotor, and which follows the shape of the chamber within the rotor housing while the rotor rotates about a tilted axis with respect to said housing.

Other objects and advantages of the invention will become apparent during the course of the following description of the accompanying drawing wherein:

FIGURE 1 is a top end elevational view of the compressor unit showing the manner in which the intake and exhaust force on opposite sides of the rotor are connected to eliminate reverse travel of the fluid or gas in the compressor unit.

FIGURE 2 is a side elevational view of the rotary compressor showing the porting arrangement and the manner in which the circumferentially divided casing sections are bolted together.

FIGURE 3 is a vertical cross-sectional view taken on line 3-3 of FIGURE 2 and looking in the direction of the arrows to illustrate the rotor and the manner in which the vane is floatingly mounted within the radial slot of the rotor.

FIGURE 4 is a cross-sectional view taken on the oblique line 44 of FIGURE 3 looking in the direction of the arrows to illustrate the sectional shape of the floatingly mounted vane and the correspondingly shaped radial slot in the rotor to support the vane in such a manner as to compensate for wear between the side walls of the vane and the walls of the radial slot, as well as the outer edge wall of the vane and the inner peripheral wall of the rotor housing, and

FIGURE 5 is a fragmentary cross-sectional view taken on the oblique line 55 of FIGURE 3 looking in the direction of the arrows and illustrating one of the sealing strips mounted in a wall of the housing and the arrangement of the intake and discharge ports on opposite sides of the sealing strip.

In the drawing, and more in detail, there is shown a compressor or pump housing generally designated 5 and a rotor generally designated 6. The compressor or pump housing 5 is formed by a pair of substantially identical casing sections 7 which can be molded or otherwise formed and then angularly displaced one to the other. Each of the compressor casings or housings are provided with radially extending flanges 8 which are secured together by circumferentially spaced fastener elements 9 such as the bolts 10 having threaded on one end thereof fastening nuts 11.

Each of the compressor casing or housing sections 7 is formed or cast with an obliquely extending hub portion 10 having bores 11 which are coaxial and are enlarged as at 12 for receiving the inner and outer race members of ball bearing assemblies 13 forming antifriction bearings for a rotary shaft 14 which extends through an opening 15 in a cover plate 16 and has its opposite end ,17 extending into the enlarged portion 12 where it is protected by a cover plate 18.

The shaft 14 is adapted to be driven by a small motor and by reason of thestructure of the compressor and the arrangement of the various parts a motor of the printed circuit type can be used without unduly overloading the same.

Each of the compressor or housing sections 7 is formed with outwardly converging walls 20 and 21 forming an annular compressor chamber 22 in which the opposed radial walls taper slightly in an outward radial direction and in a direction inward toward the peripheral walls 23 and 24 of the compressor housing 5. The inner surface of the peripheral walls 23 and 24 is arcuately curved as shown in FIGURE 3 and the compressor chamber 22 thus formed is narrower at its peripheral portions than the portions adjacent the bearing bosses 10 and the axis of the bearing hubs 10 or bosses extends obliquely and 3 tilted with respect to the axis of the compressor housing or casing 5.

Mounted on the shaft 14 is the spherical hub portion 28 of the rotor disc 6 as at 30, and said disc has its hub portion 28 provided with spherical opposed walls 32 which are received in correspondingly shaped spherical recesses 33 formed in the inner walls of the circumferentially divided compressor sections 7. The rotor 36, as will be seen from FIGURE 3, is provided with radially tapered walls 35 and 36 which converge radially outward from the spherical hub portion 28 and terminate in a wall having spaced recesses 33 for receiving a split ring 39. The split ring 3h is provided with opposed flanges 46 which are received in the recesses 33 to maintain the ring in position. The sealing ring 39 is secured to the rotor 34 by means of a pin 42 which is received in an opening 43 extending radially inward from the peripheral surface of the rotor.

The disc-shaped rotor 39 is provided with a radially extending slot 44 having inwardly converging substantially radial walls (FIGURE 4) extending from the arc of the peripheral hub portions 32 to the inner peripheral surface 26 and 25 of the compressor housing 5. Mounted within the substantially radial extending slot 44 is a vane 50 which corresponds to the shape of the slot 44 and has its end walls or radial edges shaped to conform to the converging casing walls 2% and 21. The inner surface of the vane Si? is arcuately curved as at 52 so that it will engage the curved surface 53 of the slot .4 Which is a continuation of the arcuate curvature of the spherical hub portions 32 (FIGURE 4). The arcuate surface 52 of the inner edge of the piston blade 56 is provided with a slot which extends the entire length of the piston vane 50 and mounted in the slot is a packing ring 55 which is yieldingly urged in an inward radial direction by a sinuous leaf spring 56. Thus, the vane or blade 50 is fioatingly mounted in the radial slot 44- and the spring loaded sealing strip 55 urges the vane radially outward so that its converging Walls in engagement with the slot 44 will compensate for wear and the radially tapered edges 69 of the vane will likewise be compensated for wear.

The sealing ring 39 is split to provide a space 62 so that the ends of the ring engage the radially outward tapered walls of the vane 50, and the extreme edge of the blade or vane 50 is curved to conform to the arcuate shape of the inner periphery 26 of the compressor housing or casing.

The spherical portions of the hub 28 are sealed by sealing rings 70 which are received in recesses 71 in the casing sections adjacent the bearing bosses 1t) and the sealing rings 70 are backed by annular expansion springs to yieldingly urge the sealing rings 79 into engagement with the curved surface of the spherical hub portions 32.

Each of the casing sections 7 is provided at diametrical opposed points with radially extending grooves formed in the walls and 21 respectively, and said grooves extend from the annular bearing grooves 71 to the inner peripheral surface -26 of the compressor housing 5. Mounted in each of the grooves 75-76 is a spring pressed packing strip 77-78 which is adapted to yieldingly engage the inward tapered blade edges 69 of the vane 50. The rotor is provided with a series of inwardly directed radial bores 79 to counterbalance the weight of the piston vane in the rotor 30 and prevent undue vibration.

Formed in each of the inwardly converging radial walls 7 of the housing 7 on one side of the radial packing strips 77 and 78 is an intake opening 80, while a series of discharge openings 81 are formed on the opposite sides of the radial extending packing strips 77 and 78. The external surface of each radial wall '7 is provided with a housing cover 82 which is provided with a flange 83 bolted or otherwise aflixed as at $4 to the radial wall surfaces of the compressor housing. Each of the housing covers 82 is provided with a partition Wall 85 arranged on opposite sides of the intake and discharge openings and 81, and the inner edge of said partition wall is adapted to fit in sealing engagement with the external radial surfaces of the casing sections 7 when the housing covers 82 are tightened in place by the threaded fasteners 84. The partition wall 85 is integral with the casing cover and extends parallel with the sealing strips 77-78 to divide the chamber 50 into expansion and compression sections.

A branch duct may be connected to the intake side of each of the housing covers 82 by suitable ducts 91 which, as shown in FIGURE 1, are connected as at 92 to one side of the partition wall 85. The other branch section 91 would be similarly connected. The exhaust branch pipe 94 is connected to the discharge ducts 95 and as shown in FIGURE 1, the discharge ducts 95 are connected as at 96 to the housing covers 82 on the opposite sides of the partition Walls 85. Thus, it will be seen from FIGURE 5 that when the rotor 30 is rotated the vane Ed by reason of its tilt axis will be in engagement with the sealing strips 77 and 78, and that when said vane is rotated liquid or gas is drawn into the intake openings 84 and discharged from the openings 81. Assuming clockwise rotation, looking at FIGURE 2, it will be seen that the vane 50 will move from the top of the chamber and approach the radial sealing strip 78 and discharge liquid or gas through the openings 80, and when the vane passes the sealing strip 78 suction will be created in the openings 81 at the top and bottom of the chamber and simultaneously so as to discharge liquid or gas from the ports 81. Thus, a double acting pump is provided in which gas or liquid is trapped on both sides of the rotor disc 30 in front of the vane as it rotates to first discharge liquid or gas in a compressed state and to create the flow of liquid or gas into the chambers by the suction created in back of the rotary vane or piston.

Obviously, the rotor 30 is continuously rotated on an axis normal to the line 44 which is at an acute angle of approximately 15 to a radial plane extending in an intersecting relation, and through the flanges 8 of the compressor housing 5 and the spin axis of the shaft 14 is tilted at an angle of substantially the same degree with respect to the central axis of the compressor housing or casing 5.

As the rotor 30 is rotated about its spin axis the piston or vane 50 rotates within the casing walls 20-21 and 26. The vane 50 rotates about a true channelway of annular shape and is guided solely by the rotor 30 which floatingly supports the vane 50. As the vane 50 is rotated around the annular chamber the vane will follow the annular path even though the rotor assumes various angular positions during its rotation with respect to the vane position so that in effect, the vane 50 will rotate about the true axis of the housing 7 and the pumping action is created by the rotor 30 arranged on a tilt axis with respect to said true annular chamber axis.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred embodiment thereof, and that various changes in the shape, size and arrangement of parts can be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

What I claim is:

1. In a rotary pump, compressor and the like, comprising a casing having a rotor chamber provided with radially outwardly converging chamber walls connected by a curved peripheral wall, said chamber being provided With bearing bosses on its casing walls aligned with respect to one another and extending at an acute angle to the central axis of said casing, a rotary shaft supported in said bearing bosses, a rotary disc mounted in said chamber and supported on a hub portion secured to said shaft having a spherically shaped opposed hub portion on each side of said disc for being received in correspondingly shaped recesses at the inner ends of said bearing bosses, a radial slot in said rotor disc having diverging inwardly directed walls for receiving a correspondingly shaped piston vane, said piston vane being solely supported and floatingly mounted in said slot, a yielding spring member for urging said piston vane in a radial direction, and intake and discharge ports in at least one wall of said casing.

2. In a rotary pump, compressor and the like, as set forth in claim 1 wherein a sealing ring is mounted on said rotor disc to rotate therewith and seal the opposite sides of said disc, said sealing ring extending from said piston vane around the entire periphery of said disc.

3. In a rotary pump, compressor and the like, as set forth in claim 1 wherein sealing rings are arranged in the inner casing wall for sealingly engaging the spherical hub portions of said rotor disc.

4. .In a rotary pump, compressor and the like, as set forth in claim 1, wherein said intake and discharge ports are separated by a radially extending sealing strip yieldingly mounted in a channel groove in at least one wall of said chamber.

5. In a rotary pump, compressor and the like, as set forth in claim 1, wherein said intake and discharge ports are provided in the radial casing walls on opposite sides of said rotor disc and disposed diagonally, said intake and discharge ports being arranged serially and a radial sealing strip between the intake and discharge ports engaging one of the tapered walls of said disc.

6. In a rotary pump, compressor and the like, as set forth in claim 1, wherein said rotary disc is provided with inwardly directed bores on opposite sides of said piston vane to counterbalance the increased weight of said piston vane on one side of the spin axis.

7. In a rotary pump, compressor and the like, as set forth in claim 5, wherein manifold conduits are provided for connecting the discharge and intake ports on opposite sides of said casing to permit fluid flow and the like from both chambers formed on opposite sides of said rotor disc.

References Cited by the Examiner UNITED STATES PATENTS 13,930 12/1855 Wright 103-139 789,586 5/1905 Bickerton 91-126 2,380,886 7/1945 Waldie 91-126 2,464,736 3/1949 Waldie 103-139 DONLEY I. STOCKING, Primary Examiner.

25 W. J. GOODLIN, Assistant Examiner.

Easter 103-117 

1. IN A ROTARY PUMP, COMPRESSOR AND THE LIKE, COMPRISING A CASING HAVING A ROTOR CHAMBER PROVIDED WITH RADIALLY OUTWARDLY CONVERGING CHAMBER WALLS CONNECTED BY A CURVED PERIPHERAL WALL, SAID CHAMBER BEING PROVIDED WITH BEARING BOSSES ON ITS CASING WALLS ALIGNED WITH RESPECT TO ONE ANOTHER AND EXTENDING AT AN ACUTE ANGLE TO THE CENTRAL AXIS OF SAID CASING, A ROTARY SHAFT SUPPORTED IN SAID BEARING BOSSES, A ROTARY DISC MOUNTED IN SAID CHAMBER AND SUPPORTED ON A HUB PORTION SECURED TO SAID SHAFT HAVING A SPHERICALLY SHAPED OPPOSED HUB PORTION 